/**
* This file is part of ORB-SLAM2.
*
* Copyright (C) 2014-2016 Raúl Mur-Artal <raulmur at unizar dot es> (University of Zaragoza)
* For more information see <https://github.com/raulmur/Planar_SLAM>
*
* ORB-SLAM2 is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* ORB-SLAM2 is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with ORB-SLAM2. If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef LOOPCLOSING_H
#define LOOPCLOSING_H

#include "KeyFrame.h"
#include "LocalMapping.h"
#include "Map.h"
#include "ORBVocabulary.h"
#include "Tracking.h"

#include "KeyFrameDatabase.h"

#include <thread>
#include <mutex>
#include "Thirdparty/g2o/g2o/types/types_seven_dof_expmap.h"

namespace Planar_SLAM
{

    class Tracking;
    class LocalMapping;
    class KeyFrameDatabase;


    class LoopClosing
    {
    public:

        typedef pair<set<KeyFrame*>,int> ConsistentGroup;
        typedef map<KeyFrame*,g2o::Sim3,std::less<KeyFrame*>,
                Eigen::aligned_allocator<std::pair<const KeyFrame*, g2o::Sim3> > > KeyFrameAndPose;

    public:

        LoopClosing(Map* pMap, KeyFrameDatabase* pDB, ORBVocabulary* pVoc,const bool bFixScale);

        void SetTracker(Tracking* pTracker);

        void SetLocalMapper(LocalMapping* pLocalMapper);

        // Main function
        void Run();

        void InsertKeyFrame(KeyFrame *pKF);
        void RequestReset();

        // This function will run in a separate thread
        void RunGlobalBundleAdjustment(unsigned long nLoopKF);

        bool isRunningGBA(){
            unique_lock<std::mutex> lock(mMutexGBA);
            return mbRunningGBA;
        }
        bool isFinishedGBA(){
            unique_lock<std::mutex> lock(mMutexGBA);
            return mbFinishedGBA;
        }

        void RequestFinish();

        bool isFinished();
        EIGEN_MAKE_ALIGNED_OPERATOR_NEW
    protected:

        bool CheckNewKeyFrames();
        bool DetectLoop();
        bool ComputeSim3();
        void CorrectLoop();

        void SearchAndFuse(const KeyFrameAndPose &CorrectedPosesMap);

        void ResetIfRequested();
        bool mbResetRequested;
        std::mutex mMutexReset;

        bool CheckFinish();
        void SetFinish();
        bool mbFinishRequested;
        bool mbFinished;
        std::mutex mMutexFinish;

        Map* mpMap;
        Tracking* mpTracker;

        KeyFrameDatabase* mpKeyFrameDB;
        ORBVocabulary* mpORBVocabulary;

        LocalMapping *mpLocalMapper;

        std::list<KeyFrame*> mlpLoopKeyFrameQueue;

        std::mutex mMutexLoopQueue;

        // Loop detector parameters
        float mnCovisibilityConsistencyTh;


        // Loop detector variables
        KeyFrame* mpCurrentKF;
        KeyFrame* mpMatchedKF;

        std::vector<ConsistentGroup> mvConsistentGroups;
        std::vector<KeyFrame*> mvpEnoughConsistentCandidates;
        std::vector<KeyFrame*> mvpCurrentConnectedKFs;
        std::vector<MapPoint*> mvpCurrentMatchedPoints;
        std::vector<MapPoint*> mvpLoopMapPoints;
        std::vector<MapLine*> mvpCurrentMatchedLines;
        std::vector<MapLine*> mvpLoopMapLines;
        std::vector<MapPlane*> mvpCurrentMatchedPlanes;
        std::vector<MapPlane*> mvpLoopMapPlanes;
        std::vector<MapPlane*> mvpCurrentMatchedVerticalPlanes;
        std::vector<MapPlane*> mvpLoopMapVerticalPlanes;
        std::vector<MapPlane*> mvpCurrentMatchedParallelPlanes;
        std::vector<MapPlane*> mvpLoopMapParallelPlanes;

        cv::Mat mScw;
        g2o::Sim3 mg2oScw;

        long unsigned int mLastLoopKFid;

        // Variables related to Global Bundle Adjustment
        bool mbRunningGBA;
        bool mbFinishedGBA;
        bool mbStopGBA;
        std::mutex mMutexGBA;
        std::thread* mpThreadGBA;

        // Fix scale in the stereo/RGB-D case
        bool mbFixScale;


        bool mnFullBAIdx;
    };

} //namespace Planar_SLAM

#endif // LOOPCLOSING_H
